Journal of Geophysical Research: Biogeosciences最新文献

{"title":"Reversal of the Litter N Effect on Decomposition at Higher N Addition Rates","authors":"Aijun Xing,&nbsp;Haihua Shen,&nbsp;Mengying Zhao,&nbsp;Jingyun Fang","doi":"10.1029/2024JG008570","DOIUrl":"https://doi.org/10.1029/2024JG008570","url":null,"abstract":"<p>Nitrogen (N) in the litter and soil inorganic N can have contrasting effects on litter decomposition, such that the positive effects of litter N on the rate of decomposition will likely decrease with increased soil inorganic N due to possible suppression of lignin oxidase. To test this, we reciprocally buried litter collected from multiple treatments in an N addition experiment (0, 20, 50, and 100 kg N ha⁻¹ yr⁻¹). With increasing N addition, we found that the concentration of N in the litter and the availability of inorganic N in the soil increased linearly. Contrary to our expectations, the litter N effects on decomposition changed nonlinearly with the N addition, first decreasing with the N addition rates but then reversed at the highest N addition treatment. This reversal at higher N rates is mainly due to a change in soil decomposing microbes with N addition. We examined the activity of extracellular enzymes in soil and found that phenol oxidase activity was not affected by N addition, but cellulase activity increased linearly with N addition rates. We further found that the relative abundance of bacterial functional genes involved in cellulose and the abundance of soft-rot fungi that decay cellulose increased with N addition. Our study contrasts the assumption that increased soil inorganic N suppresses lignin oxidation and instead reveals an increase in cellulolytic groups and activity of cellulase; this shift in decomposing microbes mediates the litter N effects on decomposition and suggests that more slowly decomposing fractions might be less affected.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Above and Belowground Carbon Dynamics of a Degraded Mountain Peatland","authors":"Charuni Jayasekara,&nbsp;Catherine Leigh,&nbsp;Jeff Shimeta,&nbsp;Ewen Silvester,&nbsp;Samantha Grover","doi":"10.1029/2025JG008822","DOIUrl":"https://doi.org/10.1029/2025JG008822","url":null,"abstract":"<p>Peatlands are typically net CO₂ sinks and CH₄ sources under intact or undisturbed conditions due to near-surface water tables, which create anoxic conditions that limit aerobic decomposition and promote methanogenesis. However, disturbances can disrupt this balance by altering hydrology and vegetation. In Australian mountain <i>Sphagnum</i> peatlands, vegetation change is often used to assess biophysical condition, but the effects of degradation on carbon dynamics remain poorly understood. Therefore, this study aimed to investigate the above- and below-ground carbon dynamics of a degrading Australian mountain <i>Sphagnum</i> peatland. We used the manual chamber method to measure CO₂ and CH₄ fluxes from moss-present and moss-absent areas of the peatland, over six measurement occasions in the growing season, across 2 years. A 14-month in situ mesh bag incubation experiment was also conducted to assess the decomposition rates of two peat substrates (fresh and degraded) at three different depths (5, 15, and 30 cm). The results indicated that both moss-present and moss-absent areas of the peatland acted as net CO₂ sources due to lowered water table levels than intact peatlands, moss-vegetation loss, and altered peat structure. Both areas had reduced CH₄ emissions due to the low water table and the absence of aerenchyma plants in the peatland. Organic matter decomposition rates of the peatland are mainly affected by the water table level and secondarily by substrate quality and peat depth. This study concluded that the carbon balance of degrading mountain peatlands is mainly controlled by the water table level, vegetation composition, and the quality of the substrate being decomposed.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JG008822","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulating the Potential for Invasive Grass Expansion to Alter Wildfire Behavior in Southern California With WRF-Fire","authors":"Bowen Wang,&nbsp;Gavin D. Madakumbura,&nbsp;Timothy W. Juliano,&nbsp;A. Park Williams","doi":"10.1029/2024JG008574","DOIUrl":"https://doi.org/10.1029/2024JG008574","url":null,"abstract":"<p>Invasion by non-native annual grasses poses a serious threat to native vegetation in California, facilitated through interaction with wildfires. Our work is the first attempt to use the coupled fire-atmosphere model, WRF-Fire, to investigate how shifts from native, shrub-dominated vegetation to invasive grasses could have affected a known wildfire event in southern California. We simulate the Mountain Fire, which burned &gt;11,000 ha in July 2013, under idealized fuel conditions representing varying extents of grass invasion. Expanding grass to double its observed coverage causes fire to spread faster due to the lower fuel load in grasses and increased wind speed. Beyond this, further grass expansion reduces the simulated spread rate because lower heat release partially offsets the positive effects. Our simulations suggest that grass expansion may generally promote larger faster-spreading wildfires in southern California, motivating continued efforts to contain and reduce the spread of invasive annual grasses in this region.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008574","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CO2 Fluxes Driven by Floodplain Morphology and Seasonality at the Rio Bermejo, Argentina","authors":"Sophia Dosch,&nbsp;Niels Hovius,&nbsp;Aaron Bufe,&nbsp;Marisa Repasch,&nbsp;Joel Scheingross,&nbsp;Andrea Vieth-Hillebrand,&nbsp;Dirk Sachse","doi":"10.1029/2024JG008517","DOIUrl":"https://doi.org/10.1029/2024JG008517","url":null,"abstract":"<p>Natural processes drive carbon storage and release in landscapes. On river floodplains, sediment aggradation and organic matter (OM) accumulation can sequester carbon over millennial timescales, suggesting floodplains may be carbon sinks. However, how floodplain morphology and seasonality influence CO₂ release remains unclear, limiting our ability to quantify the floodplain carbon balance. We measured CO₂ outgassing fluxes and their δ¹³C values along the Bermejo River, Argentina during wet and dry seasons using nonstationary CO₂ accumulation chambers on the water surface, sediment deposited on recently exposed riverbeds, overbank deposits, and paleochannels. Moist riverbed sediments had low CO₂ fluxes, suggesting rapid equilibration with atmospheric CO₂; overbanks and paleochannels had higher CO₂ fluxes (correlated with lower δ¹³C values), indicating that fresh OM respiration. δ¹³C_CO2 values correlate with distance to the active channel and floodplain sediment depositional age. The supply of fresh OM close to the active channel leads to respiration of labile isotopically light OM. When the floodplain loses connectivity with the active channel, seasonality becomes a dominant control on CO₂ fluxes. Wet-season conditions enhance recalcitrant OM respiration from paleochannels, increasing CO₂ fluxes and δ¹³C_CO2 values. Total floodplain CO₂ fluxes average 447 ± 138 tC km⁻² yr⁻¹, dominated by wet-season respiration in paleochannels and overbanks (398 ± 155 and 465 ± 256 tC km⁻² per season). These fluxes greatly exceed heterotrophic respiration rates of OM in the active river channel (47 ± 108 tC km⁻² yr⁻¹). CO₂ emissions from sediment exceed the annual carbon storage within the river system, suggesting that the floodplain releases more carbon than transported through the channel annually.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008517","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144833220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feral Ungulate Impacts on Carbon Cycling in a Coastal Floodplain Wetland in Tropical Northern Australia","authors":"Nicholas J. Crameri,&nbsp;Lanydjana Mununggurr,&nbsp;Yirralka Rangers,&nbsp;Damian B. Gore,&nbsp;Timothy J. Ralph,&nbsp;Alex L. Pearse,&nbsp;Jack W. Hill,&nbsp;Catherine E. Lovelock,&nbsp;Emilie J. Ens","doi":"10.1029/2025JG009056","DOIUrl":"https://doi.org/10.1029/2025JG009056","url":null,"abstract":"<p>Coastal wetland ecosystems play critical roles in mitigating climate change by sequestering substantial amounts of carbon in vegetation and sediments. The Laynhapuy Indigenous Protected Area, northern Australia, includes culturally significant floodplains that support diverse coastal wetlands. The Yirralka Rangers and Yolŋu Traditional Owners who manage this region have identified invasive ungulates as a key threat to wetlands. Paperbark forests, with species known to Yolŋu as <i>raŋan</i> (<i>Melaleuca viridiflora</i>) and <i>nämbarra</i> (<i>Melaleuca cajuputi</i>), have experienced ungulate damage combined with dieback due to saltwater intrusion. Sedgelands, dominated by culturally significant <i>räkay</i> (<i>Eleocharis dulcis</i>), suffer annual soil and vegetation damage caused by invasive pigs (<i>Sus scrofa</i>) and buffalo (<i>Bubalus bubalis</i>). The Rangers and Macquarie University scientists established an ungulate exclusion fenced plot array in 2018 across a supratidal paperbark forest and sedgeland on the Gurrumuru floodplain. To assess carbon cycle impacts, belowground carbon stocks in sediments and biomass were quantified, along with greenhouse gas (GHG) emissions across the plot array. Our findings revealed fourfold higher GHG emissions (combined CO₂ and CH₄) in locations damaged by invasive ungulates compared to undamaged sites in the early dry season. Belowground biomass increased by 21%–104% within exclusion plots compared with damaged plots. No significant differences in soil organic carbon (SOC) and total nitrogen (TN) stocks or rates of litter decomposition were found between damaged and undamaged plots. This study contributes to potential carbon crediting methods focused on reducing feral ungulate impacts to wetlands, that could help fund coastal floodplain wetland management.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2025JG009056","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144814721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vegetation Productivity Responses to Compound and Individual Climatic Stressors in Drylands","authors":"Yangmingkai Li,&nbsp;Xu Lian,&nbsp;Jiangpeng Cui,&nbsp;Songbai Hong,&nbsp;Xuhui Wang","doi":"10.1029/2024JG008695","DOIUrl":"https://doi.org/10.1029/2024JG008695","url":null,"abstract":"<p>Dryland ecosystems are a critical component of the terrestrial carbon cycle and host a significant portion of the world's biodiversity. Under anthropogenic warming, these water-limited ecosystems are increasingly threatened by the more frequent and severe heatwaves and often co-occurring droughts (known as compound hot-dry extremes). However, the respective impacts of heat and water stress on ecosystems functioning in drylands during compound extremes remain unexplored. Using satellite-observed solar-induced chlorophyll fluorescence as a proxy for vegetation productivity, our study examined its response to variations of soil moisture and air temperature by separating conditions where the two climatic factors are coupled (hot and dry) or decoupled (hot but not dry, dry but not hot). The decoupled conditions confirm soil moisture as the predominant control of dryland ecosystem productivity. However, temperature acts as a significant modulator of the moisture control particularly under wet or dry extremes: high temperatures amplify both the adverse effect of dry extremes and the positive effect of wet extremes. The productivity sensitivity to temperature and water varies strongly across regions and vegetation types, with deeper-rooted vegetation exhibiting stronger resistance to hot-dry extremes. With more frequent occurrence of hot-dry extremes under global warming, this trend leads to more negative productivity anomalies and leaves a footprint on the trajectory of productivity changes in drylands. This study highlights the additional heat-water stress on dryland ecosystems by compound hot-dry extremes superimposed on that from anthropogenic warming and drying, which adversely impact photosynthetic activities and increasingly counteract the beneficial CO₂ fertilization effect.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144814720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-Scale Variability of Blue Carbon in Seagrass Sediments From Three California Estuaries","authors":"Lena R. Capece,&nbsp;Alyssa J. Griffin,&nbsp;Melissa A. Ward,&nbsp;Aurora M. Ricart,&nbsp;Priya Shukla,&nbsp;Jolie Lobrutto,&nbsp;Tessa M. Hill","doi":"10.1029/2024JG008526","DOIUrl":"https://doi.org/10.1029/2024JG008526","url":null,"abstract":"<p>Seagrass meadows are a significant global carbon sink. Most of the carbon sequestered in these ecosystems is found as sedimentary organic carbon, which can vary spatially across seagrass meadows and can be derived from a variety of sources. Here, we investigate intra- and inter-meadow spatial variability in sediment organic carbon storage and quantify potential organic matter sources in three <i>Zostera marina</i> seagrass meadows spanning three estuaries across California (USA). Seagrass sediment organic carbon storage varies as much intra-meadow as it varies across regions. At the intra-meadow scale we find significant correlations between organic carbon content and mud content (fraction of sediment grains &lt;63 μm, %), C/N ratios and δ¹³C values in surface sediments across two meadows. At the regional scale greater organic carbon storage in the presence of seagrass compared to adjacent unvegetated sediments. Additionally, we find that mud content is the best predictor of sediment organic carbon content at the regional scale, indicating an enhanced role for mineral interaction in organic carbon preservation, but not consistently at the localized meadow scale. Approximately one fourth of organic carbon preserved in seagrass sediments is derived from seagrass. This research provides insights into the variability of organic carbon storage in seagrass meadows in California at multiple spatial scales. We demonstrate the need to account for small-scale variation of organic carbon storage in seagrass meadows to better estimate the capacity for these ecosystems to serve as effective long-term carbon sinks.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008526","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144811065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disturbance Drives Leaf Litter Leachate Dynamics in a Tropical Stream Ecosystem","authors":"Alicia A. Dixon,&nbsp;Adam S. Wymore,&nbsp;Valerie Schopfer,&nbsp;William H. McDowell","doi":"10.1029/2024JG008701","DOIUrl":"https://doi.org/10.1029/2024JG008701","url":null,"abstract":"<p>Tropical rainforests in many regions are experiencing an increased frequency of severe hurricanes and droughts due to climate change, which can alter the quantity and quality of organic matter inputs entering tropical freshwater ecosystems through inputs of leaf litter. This study leached dried senesced and freshly abscised leaves in a controlled laboratory setting as proxies of drought- and hurricane-induced changes to leaf litter inputs, respectively. The nine species that were leached are representative of the dominant riparian vegetation across most of the Luquillo Mountains of Puerto Rico. Leachate analytics, including forms of carbon, nitrogen, and major cations and anions, were analyzed across leaf condition and species to assess relationships between climatic events, species type, and leaf leachate composition. Total accumulation of solutes and concentrations of dissolved organic matter and major ions were about 2–4 times higher in leachate from dried senesced leaves (i.e., drought litter inputs) than freshly abscised leaves (i.e., hurricane litter inputs); however, the magnitudes of these differences were highly variable across species, potentially connected to leaf tissue chemistry. These data allow for scaling the impact of riparian leaf litter inputs to further our understanding of the biogeochemical and metabolic response of tropical streams to increasingly frequent climatic disturbances.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144782299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wildfire and Permafrost Thaw Reduce C Pools and Diminish Carbon Sequestration Potential in Yedoma Surface Soils","authors":"Brian Izbicki,&nbsp;Xanthe J. Walker,&nbsp;Heather D. Alexander,&nbsp;Eric Borth,&nbsp;Rebecca E. Hewitt,&nbsp;Nikita Zimov,&nbsp;Michelle C. Mack","doi":"10.1029/2024JG008631","DOIUrl":"https://doi.org/10.1029/2024JG008631","url":null,"abstract":"<p>Permafrost is increasingly vulnerable to thaw and collapse because of Arctic climate warming and wildfire activity. Arctic permafrost holds one third of global soil carbon (C) and large nitrogen (N) pools. A majority of permafrost organic matter is in the Russian Yedoma Domain. Soils in this remote region have high mineral soil C and N concentrations and massive, patterned ice wedges susceptible to degradation after disturbance. Yet, how Yedoma C and N pools will respond to the interaction of climate warming, wildfire, and permafrost thaw remains unknown. Here, we examined fire and permafrost thaw impacts in the Yedoma Domain of far northeast Siberia forests burned in 2001. We measured C and N pools, soil characteristics, and foliar chemistry and productivity. We found burning reduced soil organic layer depth, promoted active layer deepening, and initiated ground subsidence. Active layer permafrost thaw resulted in a 50% reduction in soil C pools in the top 125 cm, supported by evidence of increased decomposition from soil C isotope signatures and declining C:N. Burning and subsidence similarly diminished total soil N pools 50%, labile N pools 75%, and foliar N. Foliar N isotope signatures became more depleted after disturbance, suggesting greater reliance on mycorrhizal uptake and/or NO₃⁻. Collectively, permafrost thaw mobilized soil organic matter, reducing soil C storage, N pools, and overall nutrient capital. Permafrost collapse is not only a significant atmospheric C source but N cycle restrictions could further diminish long-term C sequestration potential which balances permafrost C loss as the ecosystem recovers from disturbance.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144782300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Between a Rock and a Soft Place: Biomass δ15N Values of Yellowstone Hot Spring Microbial Communities and Their Potential for Preservation in the Rock Record","authors":"J. R. Havig,&nbsp;T. L. Hamilton","doi":"10.1029/2024JG008136","DOIUrl":"https://doi.org/10.1029/2024JG008136","url":null,"abstract":"<p>Nitrogen isotope (δ¹⁵N) values in ancient rocks have been used to interpret the presence of nitrogen metabolisms and fixed N availability across the Archean and Paleoproterozoic eons. However, how δ¹⁵N signals produced by nitrogen metabolisms of microbial communities, the impact of the geochemical environments they live in on those signals, and the fidelity of those signals through preservation in the rock record have not been fully constrained and validated. Thus, it is imperative to study modern microbial systems to test the validity of using δ¹⁵N signals produced by microbial communities to interpret what geochemical environments and nitrogen metabolisms influenced the production of those signals. Hydrothermal systems are an ideal place to examine the biotic and abiotic factors that impact δ¹⁵N signals—physical processes generate geochemical environments with wide ranges of fixed N availability and the physicochemical environments exclude multicellular eukaryotic organisms. Previous work has demonstrated the presence of nitrogen fixation genes in microbial communities across a range of temperature (16–89°C) and pH (1.9–9.8) gradients. Here, we test the validity and fidelity of using microbial community δ¹⁵N signals as indicators of geochemical environment and nitrogen metabolisms (specifically, biological nitrogen fixation) present in eight hydrothermal systems across Yellowstone National Park. Our results suggest that δ¹⁵N values measured in the ancient rock record can provide information about the N cycling and prevailing environmental conditions during deposition, but only if viewed within appropriate context.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 8","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008136","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144782298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}